First of all, I have to say thanks to all the response I have gotten! From what I have read, it's looks like quite a challenge to use digital cameras to capture the shot flying past and then have usable data to calculate positions. I think I am going to try to use the paper scanning method. The paper we use already comes on a roll. I will probably try to use a 4 foot fluorescent bulb for a backlight to a giant fax machine scanner. Yes, once this process is sped up, we would like to use multiple shots from the same combination to estimate variability. And, for now, I am going to ignore the 3-D pattern, just too much to deal with. I will get back to you with more when this is out of the vaporware stage. Thanks and more thanks. Tony -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics